techfun89 writes: "Mars has returned to our evening skies as it does every two years. This time it is getting even more attention and buzz than it normally would. Amateur astronomer Wayne Jaeschke of West Chester Pennsylvania noticed an unusual protrusion in the planet's southern hemisphere, preceding the sunrise terminator.

Several things may have contributed to this strange "cloud formation". One possibility is a meteoric impact event, where dust was spewed up into the atmosphere. Another could be a major dust storm, which are typical on Mars. While the other possibility is the more mundane, that these observations were caused by a mere optical illusion via a type of glint that occurred due to having just the right combination of lighting and atmospheric conditions. Some suggest volcanic activity, though this is unlikely given it has been 20 to 200 million years since lava has flowed on Mars."Link to Original Source